1. Field of the Invention
The present invention relates to a multi-image file editing apparatus and a multi-image file editing method for editing a multi-image file including main image data and one or more sub-image data.
2. Description of Related Art
At the time of shooting images, one image is shot for each scene in some cases, while in other cases a plurality of images are shot by a predetermined shooting sequence such as sequential shooting, panoramic shooting, auto-bracket shooting, and multiple-viewpoint shooting (what is called stereoscopic vision image shooting). Since recent digital cameras, in particular, have improved sequential shooting performance, the number of images obtained by sequential shooting tends to dramatically increase. However, if images obtained by sequential shooting are recorded as individual files, respectively, file management is likely to be very cumbersome.
To eliminate such disadvantage, a technique is proposed to obtain a high convenience in file operation and management by handling a group of images which are obtained by such a predetermined shooting sequence and the like and highly related to one another as a single file rather than handling the group of images as individual files.
Incidentally, digital still images obtained by image pickup operation are saved as JPG files complying with the JPEG standard in many cases at present, and “JPG” is used as the extension of the files. In order to maintain file compatibility with existing image processing apparatuses and JPG applications which are designed to handle the JPG files, it is required to append the extension “JPG” to the files. Furthermore, it is also required that the internal structure of the files complies with the Exif standard as a de facto standard in digital cameras, and the like.
Techniques that satisfy these requirements at the same time include one disclosed in Japanese Patent Application Laid-Open Publication No. 2005-252754, for example. The technique disclosed in the publication is such that a plurality of JPEG images are put together into one file to prevent an increase in the number of files, and a main image (one main (representative) image among the plurality of images put together into the one file) is stored at the head of the file in a format complying with the Exif standard, and the extension “JPG” is appended to the file itself.
Specifically, the file as shown in FIG. 10 is created. FIG. 10 is a view showing an exemplary configuration of a conventionally proposed image file which is capable of storing a plurality of JPEG image data. The image file can store one JPEG image data as the main image and other n (n is an integer equal to or larger than 1) pieces of JPEG image data as sub-images other than the main image, for example. A JPEG header is added to each of the JPEG images, and one set composed of the JPEG header and the JPEG image data is configured to be sandwiched between an image start marker SOI and an image end marker EOI. In such a configuration, the image stored at the head of the image file is the main image. In the JPEG header of the main image are stored information on each of the sub-images stored in the same image file (for example, a total number of the sub-images, identification numbers of the sub-images (which number of the sub-images in the image file), pointers to the sub-images, image type information of the sub-images (which is information indicative of the relationship between the main image data and one or more sub-images at the time of shooting, specifically, information indicating that each of the sub-images is obtained by panoramic shooting or bracket shooting and the like). In addition, the extension of the file name is “JPG” (the file name of the example shown in the drawing is “hogehoge.JPG”).
Such a configuration employed in the file for storing a plurality of JPEG image data, in which the extension is “JPG” and the part from the head of the file to the end of the main image has the same structure as that of the existing JPEG format, maintains compatibility with existing image processing apparatuses and applications that handle JPG files. Since a plurality of image data are stored in one file, there are advantages that the number of files can be reduced and file management becomes easier. The file, one example of which is shown in FIG. 10, i.e., the image file for storing a plurality of image data in one file is hereinafter called “multi-image file” as needed.
To the contrary, the existing Exif standard is defined such that only one JPEG image, excepting a thumbnail image, is stored for one JPG file.
The file for storing a plurality of images as disclosed in the Japanese Patent Application Laid-Open Publication No. 2005-252754 can be displayed, edited and saved using the existing image processing apparatus and application as described above, since the main image at the head of the file maintains compatibility with an existing JPG file. However, when the JPG file as disclosed in the publication is edited and saved using the existing image processing apparatus and application complying with the above-described current Exif standard, there is a possibility that only the main image is saved but sub-images other than the main image are deleted or damaged.
Therefore, in order to reproduce, edit, or distribute images using the existing image processing apparatus and application, a utilizing method for dividing the images in the multi-image file into individual JPG files can be considered. The multi-image file as disclosed in the Japanese Patent Application Laid-Open Publication No. 2005-252754 has a configuration in which a plurality of JPG files are united as one file, thereby facilitating such a division.
However, if once the multi-image file is divided, the relationship among image groups which are managed as one file is lost. Therefore, it is very difficult to unite the divided files into one again.